View Compilation Error

170044_0_6366.cpp:9: error: `main' must return `int'
170044_0_6366.cpp: In function `int main(...)':
170044_0_6366.cpp:31: error: `prlongf' undeclared (first use this function)
170044_0_6366.cpp:31: error: (Each undeclared identifier is reported only once for each function it appears in.)